1. Field of the Invention
The present invention relates generally to a method and an apparatus for supporting a large Service Data Unit (SDU) in a mobile communication system.
2. Description of the Related Art
General wireless communication systems (or networks) provide access to multiple users with respect to at least one shared resource (e.g., bandwidth, transmission power, etc.). For example, the systems adopt various multiple access technologies, such as Frequency Division Multiplexing (FDM), Time Division Multiplexing (TDM), Code Division Multiplexing (CDM), Orthogonal Frequency Division Multiplexing (OFDM), a 3GPP Long Term Evolution (LTE) system, etc.
The protocol stack of the Long Term Evolution (LTE) system using OFDM generally includes three parts, i.e., a Medium Access Control (MAC) layer, a Radio Link Control (RLC) layer, and a Packet Data Convergence Protocol (PDCP).
Most current computer systems are based on a Maximum Transfer Unit (MTU) of 1500 bytes. Accordingly, a maximum length of one RLC SDU is configured to have an 11 bit-length, i.e., 2047 bytes in the LTE system. Therefore, in order to transmit a large amount of data, e.g., more than 2047 bytes, fragmentation is performed in the upper layer, i.e., an Internet Protocol (IP) layer, of the LTE system.
Currently, most of the MTUs of the LTE upper systems are configured to 1500 bytes, which is not always problematic. However, the LTE protocol stack will still need to be taken into consideration in order to support an upper system configured with an MTU having a size that exceeds 1500 bytes, e.g., 2047 bytes, in the future.